JHANG, Pakistan (Reuters) - When Maulana Ahmed Ludhianvi greets supporters on the Pakistan election trail, he opens his pitch with the kind of promises to the poor that any other politician might make.

But behind the reassuring rhetoric lies what his opponents believe is a dangerous agenda - to gain a foothold in parliament and further his designs to oppress Pakistan's Shi'ite minority.

Ludhianvi, a radical Sunni cleric, is a hate figure for Shi'ites who accuse him of devoting his decades-long career to fomenting an escalating campaign of gun attacks and suicide bombings targeting their community.

The prospect that he might win a place in the political mainstream at the May 11 vote horrifies Shi'ites who fear his presence in parliament will give him a much stronger platform to strike out at the sect.

And it looks like Ludhianvi may have a better shot than at the last election in 2008 when he came second. His main rival has been barred from the race and a Reuters visit to his constituency of Jhang, in the heart of populous Punjab province, found no shortage of supporters.

"I cannot bring any change if I am sitting as a layman outside parliament," Ludhianvi, flanked by bodyguards, said in an interview. "If I get into parliament, everyone will be listening to what we want."

As he toured Jhang, which served as the cradle of sectarian extremist groups in the 1980s, people in one village after another emerged from their homes to shower him with rose petals.

"If I get into parliament, I will be able to save this entire country from bloodshed," said Ludhianvi, who wears a thick beard and an embroidered skull cap and projects a commanding presence.

The election is seen as a milestone for Pakistan's fragile democracy, marking the first time a civilian government has completed a full term in a country which a long history of military meddling in politics.

Western powers are hoping the polls might deliver a government capable of grappling with huge domestic challenges and helping the United States bring the Afghan Taliban to the negotiating table ahead of a NATO pullout in 2014.

Any triumph by Ludhianvi at the polls could be read as a sign that sectarianism - now seen as a top security threat - has made a troubling new in-road into the political sphere, which could further polarise the nuclear-armed country.

Ludhianvi was a leader of Sipah-e-Sahaba, a sectarian Sunni group which emerged in Jhang in the mid-1980s with the support of Pakistani intelligence and which has since been linked to hundreds of killings of Shi'ites.

The group's offshoot, Lashkar-e-Jhangvi (LeJ), evolved into one of Pakistan's most feared militant groups and has claimed responsibility for many attacks on Shi'ites, including a series of bombings that killed almost 200 people in the southwestern city of Quetta this year.

Police in Karachi, the commercial capital, suspect LeJ or similar groups are behind a wave of gun attacks on Shi'ites.

Pakistan banned Sipah-e-Sahaba in 2001 under pressure from the United States to crack down on militancy but the group changed its name to Ahle Sunnat Wal Jamat (ASWJ), which Ludhianvi heads.

Pakistan's sectarian fringe has long been plagued by divisions which make it hard to determine what role individual leaders play. But security officials see Ludhianvi as a member of a core group of ideologues whose anti-Shi'ite views have served as a source of inspiration for militants, though he denies any role in violence.

SUNNI-SHI'ITE DIVIDE

The military has in the past quietly supported Islamist politicians and parties in the interest of its own political agenda but it is not clear what stand the military-run security agencies that watch domestic politics are taking this time.

The army chief, General Ashfaq Kayani, has avoided the overt meddling in politics of many of his predecessors and repeatedly insisted the election must be free and fair.

The schism between Sunnis and Shi'ites developed after the Prophet Muhammad died in 632 when his followers could not agree on a successor.

Emotions over the issue have boiled in modern times and even pushed some countries to the brink of civil war. Pakistan is nowhere close to that, but security officials say groups like the LeJ and Sipah-e-Sahaba are stepping up their bloody campaign to persecute Shi'ites and are destabilising the country.

These days, Ludhianvi is careful to portray himself as a man of peace and is waging a populist campaign to capitalise on resentment of Shi'ite landowners. Coming himself from a modest background, he has vowed to build schools, hospitals and roads.

"This is a tribal area which was ruled by a few rich people who used to treat the poor people like slaves," said Ludhianvi.

"There is no education system or schools for girls and boys. Nobody even tries to build schools or colleges."

But other senior members of his ASWJ party are more vocal about their desire to restrict the rights of Shi'ites.

Aurangzeb Farooqi, head of the party in Karachi, told Reuters in January that Shi'ites should be barred from holding important public office and their public religious activities should be restricted. Farooqi is also running for a seat in the national assembly.

In Jhang, Ludhianvi's blend of populism and sectarianism has earned him considerable grassroots appeal. He won 45,000 votes at the 2008 election, placing him second to Sheikh Waqas who won with 52,000 votes.

But Waqas has been barred from this election on the grounds that he had presented a fake education certificate, raising Ludhianvi's chances of victory.

Politicians are taking note. Rather than making alliances with big businessmen or going door-to-door for votes, aspiring office holders like Azad Ansari, who is in the wool industry, are rallying behind Ludhianvi.

Ansari once served in the secular PML-N but now hopes Ludhianvi can help him make a mark in politics.

"I will get more popular if I join him," Ansari said.

Such sentiment has fostered a perception that leaders of the PML-N party, which controls Punjab, have deliberately been soft on sectarian groups for fear of alienating potential voters.

These suspicions were compounded when Rana Sanaullah, Punjab's law minister and a PML-N stalwart, campaigned alongside Ludhianvi at a by-election rally in Jhang in 2010.

The spectacle of Ludhianvi reinventing himself sends chills through the Shi'ite community, which may make up to 20 percent of the population, though some estimates put the number lower.

"What can Ludhianvi do? He will do nothing but spread terrorism," said Raza Hussain, a resident of a Shi'ite neighbourhood of Jhang.

Some fear that a victory for Ludhianvi and other hardliners at the polls will provide a veneer of political cover for violent sectarian extremists.

"This could be very dangerous," said Amir Rana, an expert on Pakistani militancy. "This would give all of their activities political legitimacy."

But some security officials argue that bringing leaders like Ludhianvi into conventional politics may be a way to weaken the sectarian threat by isolating the most violent elements.

Conscious of the need to project a respectable image, Ludhianvi is careful to avoid the kind of inflammatory rhetoric favoured by many in his party.

But the presence of young men wearing headbands with the symbols of banned anti-Shi'ite groups, who hung on Ludhianvi's every word during his whistle-stop tour, keeps Shi'ites on edge.

"He has done nothing for Jhang except terrorism," said Sheikh Hussain, a businessman. "They should be stopped."